Bilateral Transcranial Direct Current Stimulation Language Treatment Enhances Functional Connectivity in the Left Hemisphere: Preliminary Data from Aphasia

2016 ◽  
Vol 28 (5) ◽  
pp. 724-738 ◽  
Author(s):  
Paola Marangolo ◽  
Valentina Fiori ◽  
Umberto Sabatini ◽  
Giada De Pasquale ◽  
Carmela Razzano ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Left Hemisphere ◽  
Direct Current ◽  
Transcranial Direct Current Stimulation ◽  
Broca’S Area ◽  
Broca's Area ◽  
Direct Current Stimulation ◽  
Sham Condition ◽  
Study Results ◽  
The Right

Several studies have already shown that transcranial direct current stimulation (tDCS) is a useful tool for enhancing recovery in aphasia. However, no reports to date have investigated functional connectivity changes on cortical activity because of tDCS language treatment. Here, nine aphasic persons with articulatory disorders underwent an intensive language therapy in two different conditions: bilateral anodic stimulation over the left Broca's area and cathodic contralesional stimulation over the right homologue of Broca's area and a sham condition. The language treatment lasted 3 weeks (Monday to Friday, 15 sessions). In all patients, language measures were collected before (T0) and at the end of treatment (T15). Before and after each treatment condition (real vs. sham), each participant underwent a resting-state fMRI study. Results showed that, after real stimulation, patients exhibited the greatest recovery not only in terms of better accuracy in articulating the treated stimuli but also for untreated items on different tasks of the language test. Moreover, although after the sham condition connectivity changes were confined to the right brain hemisphere, real stimulation yielded to stronger functional connectivity increase in the left hemisphere. In conclusion, our data provide converging evidence from behavioral and functional imaging data that bilateral tDCS determines functional connectivity changes within the lesioned hemisphere, enhancing the language recovery process in stroke patients.

Transcranial direct current stimulation (tDCS) of Broca's area in chronic aphasia: A controlled outcome study

2013 ◽  
Vol 247 ◽  
pp. 211-216 ◽  
Author(s):  
Chiara Volpato ◽  
Marianna Cavinato ◽  
Francesco Piccione ◽  
Martina Garzon ◽  
Francesca Meneghello ◽  
...  
Keyword(s):  
Direct Current ◽  
Transcranial Direct Current Stimulation ◽  
Outcome Study ◽  
Broca’S Area ◽  
Broca's Area ◽  
Direct Current Stimulation ◽  
Chronic Aphasia

scholarly journals Cerebellar transcranial direct current stimulation reconfigurates static and dynamic functional connectivity of the resting-state networks

2020 ◽  
Author(s):  
Fatma Grami ◽  
Giovanni de Marco ◽  
Florian Bodranghien ◽  
Mario Manto ◽  
C. Habas
Keyword(s):  
Functional Connectivity ◽  
Direct Current ◽  
Transcranial Direct Current Stimulation ◽  
Resting State ◽  
Cortical Excitability ◽  
Region Of Interest ◽  
Temporal Variations ◽  
Functional Changes ◽  
Direct Current Stimulation ◽  
The Right

Abstract Background Transcranial direct current stimulation (tDCS) of the cerebellum dynamically modulates cerebello-thalamo-cortical excitability in a polarity-specific manner during motor, visuo- motor and cognitive tasks. It remains to be established whether tDCS of the cerebellum impact also on resting-state intrinsically connected networks (ICNs). Such impact would open novel research and therapeutical doors for the neuromodulation of ICNs in human. Method: We combined tDCS applied over the right cerebellum and fMRI to investigate tDCS- induced resting-state intrinsic functional reconfiguration, using a randomized, sham-controlled design. fMRI data were recorded both before and after real anodal stimulation (2 mA, 20 min) or sham tDCS in 12 right-handed healthy volunteers. We resorted to a region-of-interest static correlational analysis and to a sliding window analysis to assess temporal variations in resting state FC between the cerebellar lobule VII and nodes of the main ICNs. Results After real tDCS and compared with sham tDCS, functional changes were observed between the cerebellum and ICNs. Static FC showed enhanced or decreased correlation between cerebellum and brain areas belonging to visual, default-mode (DMN), sensorimotor and salience networks (SN) (p-corrected < 0.05). The temporal variability (TV) of BOLD signal was significantly modified after tDCS displaying in particular a lesser TV between the whole lobule VII and DMN and central executive network and a greater TV between crus 2 and SN. Static and dynamic FC was also modified between cerebellar lobuli. Conclusion These results demonstrate short- and long-range static and majorly dynamic effects of tDCS stimulation of the cerebellum affecting distinct resting-state ICNs, as well as intracerebellar functional connectivity, so that tDCS of the cerebellum appears as a non-invasive tool reconfigurating the dynamics of ICNs.

Effects of Transcranial Direct Current Stimulation on Apraxia of Speech and Cortical Activation in Patients With Stroke: A Randomized Sham-Controlled Study

2019 ◽  
Vol 28 (4) ◽  
pp. 1625-1637 ◽  
Author(s):  
Jie Wang ◽  
Dongyu Wu ◽  
Yinan Cheng ◽  
Weiqun Song ◽  
Ying Yuan ◽  
...  
Keyword(s):  
Direct Current ◽  
Transcranial Direct Current Stimulation ◽  
Primary Motor Cortex ◽  
Approximate Entropy ◽  
Cortical Activation ◽  
Controlled Study ◽  
Broca’S Area ◽  
Apraxia Of Speech ◽  
Broca's Area ◽  
Direct Current Stimulation

Purpose The study aims to investigate, using anodal transcranial direct current stimulation (A-tDCS), over which site, the left lip region of primary motor cortex (M1) or the Broca's area, there would be better recovery from apraxia of speech (AoS) in patients with poststroke aphasia and to examine for altered activation in speech-related areas after tDCS with nonlinear electroencephalography (EEG). Method Fifty-two patients with AoS were randomized into A-tDCS over the left M1 (A-tDCS-M1), Broca's area, and sham tDCS groups who underwent 10 sessions of tDCS and speech treatment for 5 days. The EEG nonlinear index of approximate entropy was calculated for 6 subjects in each group before and after treatment. Results After treatment, the change in speech-language performance improved more significantly in the A-tDCS-M1 group than the other 2 groups ( p < .05). EEG approximate entropy indicated that both A-tDCS groups could activate the stimulated sites; the improvement in the A-tDCS-M1 group was correlated with high activation in the dorsal lateral prefrontal cortex and Broca's areas of the left hemisphere in addition to the stimulated site. Conclusion A-tDCS over the left M1 can improve the speech function in patients with poststroke aphasia and severe AoS and excite and recruit more areas in the motor speech network.

scholarly journals Cerebellar transcranial direct current stimulation reconfigurates static and dynamic functional connectivity of the resting-state networks

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
F. Grami ◽  
G. de Marco ◽  
F. Bodranghien ◽  
M. Manto ◽  
C. Habas
Keyword(s):  
Functional Connectivity ◽  
Direct Current ◽  
Transcranial Direct Current Stimulation ◽  
Resting State ◽  
Cortical Excitability ◽  
Region Of Interest ◽  
Temporal Variations ◽  
Functional Changes ◽  
Direct Current Stimulation ◽  
The Right

Abstract Background Transcranial direct current stimulation (tDCS) of the cerebellum dynamically modulates cerebello-thalamo-cortical excitability in a polarity-specific manner during motor, visuo- motor and cognitive tasks. It remains to be established whether tDCS of the cerebellum impact also on resting-state intrinsically connected networks (ICNs). Such impact would open novel research and therapeutical doors for the neuromodulation of ICNs in human. Method We combined tDCS applied over the right cerebellum and fMRI to investigate tDCS- induced resting-state intrinsic functional reconfiguration, using a randomized, sham-controlled design. fMRI data were recorded both before and after real anodal stimulation (2 mA, 20 min) or sham tDCS in 12 right-handed healthy volunteers. We resorted to a region-of-interest static correlational analysis and to a sliding window analysis to assess temporal variations in resting state FC between the cerebellar lobule VII and nodes of the main ICNs. Results After real tDCS and compared with sham tDCS, functional changes were observed between the cerebellum and ICNs. Static FC showed enhanced or decreased correlation between cerebellum and brain areas belonging to visual, default-mode (DMN), sensorimotor and salience networks (SN) (p-corrected < 0.05). The temporal variability (TV) of BOLD signal was significantly modified after tDCS displaying in particular a lesser TV between the whole lobule VII and DMN and central executive network and a greater TV between crus 2 and SN. Static and dynamic FC was also modified between cerebellar lobuli. Conclusion These results demonstrate short- and long-range static and majorly dynamic effects of tDCS stimulation of the cerebellum affecting distinct resting-state ICNs, as well as intracerebellar functional connectivity, so that tDCS of the cerebellum appears as a non-invasive tool reconfigurating the dynamics of ICNs.

scholarly journals Cathodal Transcranial Direct Current Stimulation Over the Right Temporoparietal Junction Suppresses Its Functional Connectivity and Reduces Contralateral Spatial and Temporal Perception

2021 ◽  
Vol 15 ◽  
Author(s):  
Guo Dalong ◽  
Li Jiyuan ◽  
Zhou Yubin ◽  
Qin Yufei ◽  
Yang Jinghua ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Direct Current ◽  
Transcranial Direct Current Stimulation ◽  
Spatial Perception ◽  
Insular Cortex ◽  
Temporoparietal Junction ◽  
Direct Current Stimulation ◽  
Right Temporoparietal Junction ◽  
The Right ◽  
Self Motion

The temporoparietal junction plays key roles in vestibular function, motor-sensory ability, and attitude stability. Conventional approaches to studying the temporoparietal junction have drawbacks, and previous studies have focused on self-motion rather than on vestibular spatial perception. Using transcranial direct current stimulation, we explored the temporoparietal junction’s effects on vestibular-guided orientation for self-motion and vestibular spatial perception. Twenty participants underwent position, motion, and time tasks, as well as functional magnetic resonance imaging scans. In the position task, cathodal transcranial direct current stimulation yielded a significantly lower response in the −6, −7, −8, −9, −10, −11, and −12 stimulus conditions for leftward rotations (P &lt; 0.05). In the time task, the temporal bias for real transcranial direct current stimulation significantly differed from that for sham stimulation (P &lt; 0.01). Functional magnetic resonance imaging showed that cathodal transcranial direct current stimulation suppressed functional connectivity between the temporoparietal junction, right insular cortex, and right supplementary motor area. Moreover, the change in connectivity between the right temporoparietal junction seed and the right insular cortex was positively correlated with temporal bias under stimulation. The above mentioned results show that cathodal transcranial direct current stimulation induces immediate and extended vestibular effects, which could suppress the functional connectivity of the temporoparietal junction and in turn reduce contralateral spatial and temporal perception. The consistent variation in temporal and spatial bias suggested that the temporoparietal junction may be the cortical temporal integrator for the internal model. Moreover, transcranial direct current stimulation could modulate the integration process and may thus have potential clinical applications in vestibular disorders caused by temporoparietal junction dysfunction.

Sign in / Sign up

Export Citation Format

Share Document